The Casa da Música is situated on a travertine plaza,
between the city's historic quarter and a working-class
neighborhood, adjacent to the Rotunda da Boavista.

The square is no longer a mere hinge between the old and the new
Porto, but becomes a positive encounter of two different models of
the city.

Photo: Charlie Koolhaas

By considering the building as a solid mass, from
which we eliminated the two concert halls and all other public
facilities, we created a hollowed-out block that reveals its
contents without being didactic and, at the same time, exposes the
city. The building is both clear and mysterious - the diagram
becomes an architectural adventure./OMA

The chiselled sculptural form of the white concrete shell houses
the main 1,300 seat concert hall, a small 350 seat hall, rehearsal
rooms, and recording studios for the Oporto National Orchestra. A
terrace carved out of the sloping roofline and huge cut-out in the
concrete skin connects the building to city.

Photo: Charlie Koolhaas

Photo: Charlie Koolhaas

Stairs lead from the ground level plaza to the foyer where a
second staircase continues to the Main Hall and the different
levels above. Heavy concrete beams criss-cross the huge lightwell
above.

Photo: Charlie Koolhaas

Photo: Charlie Koolhaas

Photo: Charlie Koolhaas

Photo: Charlie Koolhaas

The main auditorium, shaped like a simple shoebox, is enclosed
at both ends by two layers of "corrugated" glass walls. The glass,
corrugated for optimal acoustics and sheer beauty, brings diffused
daylight into the auditorium.

Photo: Charlie Koolhaas

Photo: Charlie Koolhaas

During the Design Phase OMA researched new materials and new
applications of existing Portuguese materials. The walls in the
large hall are lined with plywood panels that are embossed with a
gold-leaf pattern that is an enlargement of the grain of the
plywood itself. A baroque organ is pinned to the plywood wall.

Photo: Charlie Koolhaas

Photo: Charlie Koolhaas

One room has pale-blue tiles with religious themes, commonly
found in Portuguese churches, another is clad in strongly geometric
tiles.

The folded glass "curtains" allow for slightly distorted views
of the city.

Photo: Charlie Koolhaas

The structural heart of the building is formed by four massive
walls that extend from the base to the roof and connect the tilted
external walls with the core of the structure. The two one meter
thick walls of the main auditorium act as internal diaphragms tying
the shell together in the longitudinal direction. The principal
materials are white concrete, corrugated glass, travertine,
plywood, and aluminium.